The present invention pertains to the field of video equipment and systems, and more particularly is concerned with control circuitry for automatically detecting and editing commercial messages from standard television broadcast signals.
The removal or editing of commercial messages from the reception and/or video recording of television signals has long been a goal of innovators in the video equipment industry. Thus far, little progress has been made in providing a reliable circuit or method of automatically detecting the occurrence and duration of commercial interruptions in the program content of a television signal. Such capability is particularly desirable when combined with video tape recorders used for unattended recording of off-the-air television broadcasts. The resulting recording would store the program content, skipping over those portions of the broadcast television signal that carry the commercial interruptions.
Thus far, efforts to develop such a system have been only partially successful. For example, one currently available device is effective to blank out or delete color commercials that have been interposed in black and white telecasts. The black and white television signal, is fundamentally different in content from a color broadcast signal. The available editing device is capable of detecting this difference and in response thereto produces a control signal that begins at the start of the color commercial and ends when the black and white program content resumes. The generated control signal can be used to interrupt the operation of video tape recorders that are equipped with a pause control. During the color commercial, the video recorder is momentarily stopped (placed in a pause mode) and then is automatically restarted upon termination of the control signal and hence at the resumption of the black and white program content.
Such a device has apparent limitations in that it can only be used for telecasts of black and white movies, or for early serials that were originally taped in black and white. Such devices are totally ineffective for extracting color commercials from color program content which constitutes the great majority of telecasts today.
Accordingly it is an object of the present invention to provide a commercial deleting control circuit and method that are effective to edit commercial messages from television broadcast signals in which both the commercials and the program content interrupted thereby are in color.
A more particular object of the present invention is to provide a control circuit for use with a video tape recorder for automatically interrupting the operation of the video recorder during a taping of a color television signal, so as to omit the recording of one or a succession of brief commercial messages.